2/5 sized gravel for ducks?

[MeoWusical]

Hello!
I’m thinking of getting River rocks to cover the gross mess in my ducks run. I’ve seen people use the small Pea Gravel, but it seems to get smooshed around when it gets wet
I was wondering if 2/5 inch river rocks would work well? Would it hurt their feet?

 

[Miss Lydia]

As long as there aren’t any sharp pieces it should be fine.